Steering is a term often applied to the collection of components, linkages, and the like which will allow for a driven machine to follow a desired course. Conventional steering arrangements are typically operated by a user rotating a hand-operated steering which results in the front wheels turning to the desired angle. The steering wheel is typically connected to a shaft that drives a pinion gear which then drives a rack. Steering torque is provided to the kingpins of the wheels via tie rods connected to the rack.
Ackermann steering geometry is a geometric arrangement of linkages in the steering of a machine designed to solve the problem of wheels on the inside and outside of a turn needing to trace out circles of different radii. An approximation to perfect Ackermann steering geometry may be generated by moving the steering pivot points inward so as to lie on a line drawn between the steering kingpins and the center of the rear axle. With perfect Ackermann, at any angle of steering, the centre point of all of the circles traced by all wheels will lie at a common point (where lines which are respectively perpendicular to individual tires, meet). Perfect Ackermann allows for the least amount of wear on tires, but it may be difficult to arrange in practice with simple linkages, especially for small radius turns.